One report names the substance, and the sentence follows from it.

In a Turkish drug file the substance is not proved by what officers called it at the roadside. It is proved by an expert report — a bilirkişi raporu — produced by a laboratory and placed in the file. Almost everything after that follows from two lines in it: what the substance is, and how much of it there was.

The reason is that the Penal Code attaches a fixed consequence to a name.

On a 188/3 file, a floor of ten years increased by half is a floor of fifteen. That arithmetic is performed by the word the laboratory writes on one line of a report, before anyone has argued about anything. One word decides whether the third row of that table applies or the fourth.

This is why a drug defence that begins with the account of events and gets to the report later is starting in the wrong place.

Under CMK 63, an expert opinion may be taken where the resolution of a question requires expertise or special or technical knowledge. It can be ordered by the court of its own motion, or on the application of the prosecutor, the participant, the suspect or defendant, defence counsel or a legal representative.

Two things in that article matter to a defendant. First, CMK 63/3 gives the public prosecutor the same powers during the investigation stage — a request for an examination does not have to wait for an indictment. Second, CMK 63/1 forbids resort to an expert on questions capable of being resolved by general knowledge or by the legal knowledge the judicial office requires. That sentence is the foundation of the objection that a report has answered a legal question instead of a technical one.

How the expert is selected

CMK 64 requires experts to be chosen from the list prepared by the expert-witness board for the regional court of appeal district, with a narrow route to appointing from outside the lists where no expert in the relevant field exists. Official experts designated by law for particular subjects are appointed first. Every expert swears to carry out the task in accordance with science and impartially.

The appointment decision is a document you can read

CMK 66/1 requires the decision appointing the expert to state the questions requiring expertise, the subject of the examination, and the period for completing it. That period cannot exceed three months, and can be extended by up to three further months, once, by reasoned decision on the expert's request.

Read the questions. A laboratory answers what it was asked. If the decision asked only what the substance is, the file will contain no finding on purity, no net weight of active substance, and nothing about whether the packaging arrived intact — because nobody asked.

Seals, lists and counts

CMK 66/7 requires that, before items are given to the expert under seal, a list and a count of them be made and recorded. The expert is then obliged to record the breaking and the reapplication of the seals, again by record, and to draw up a list. These documents are where the physical history of the substance between the seizure and the bench is written down. They are usually in the file and usually unread.

CMK 67/1 sets out what a report must contain: the operations the expert carried out and the conclusions reached, with an express statement that the examinations requested were performed. It is signed and delivered to the authority that ordered it, together with the sealed items.

Where more than one expert was appointed and they differ — in their views, or on parts of a shared conclusion — CMK 67/2 requires the difference and its reasons to be written into the report. A single unanimous-looking conclusion in a file where several experts were appointed is worth asking about.

The limit the Code places on the expert

CMK 67/3 is one sentence and it is the most useful sentence on this page. In the report and in oral explanations, the expert may not go beyond matters requiring expertise or special or technical knowledge, and may not make the legal characterisations and assessments that belong to the judge.

A laboratory may state what a substance is, what it weighs and what proportion of it is active. It may not state that the quantity indicates supply rather than personal use. Whether the file is TCK 188 or TCK 191 is the court's question. A report that answers it has gone past CMK 67/3, and that is a ground of objection rather than a matter of opinion.

The report does not bind the court

Under CMK 217, the judge may base a decision only on evidence brought to the hearing and discussed there, and evaluates that evidence freely according to conscientious conviction. An expert report is evidence to be weighed, not a verdict delivered early. In practice it is weighed heavily — which is why it is answered with another technical document rather than with disagreement.

CMK 67/4 allows copies of the report to be handed directly to the defendant and counsel at the hearing, or sent by registered post. If you are outside Türkiye, ask counsel for the document itself, not a summary of it.

These three figures are routinely treated as though they do the same work. They do not.

• Substance type is written into the statute. TCK 188/4-a increases the penalty by half where the substance is one of the named ones. A fixed legal consequence follows from a name.
• Weight is not. TCK 188 contains no weight threshold. There is no quantity at which the article changes, and none at which it stops applying.
• Purity is not either. TCK 188 contains no purity threshold. A report showing a low proportion of active substance does not remove the 188/4-a increase and does not move the file into a lower paragraph.

Weight and purity enter the sentence elsewhere. Under TCK 61/1 the judge fixes the basic penalty between the statutory minimum and maximum, taking into account, among other things, the manner in which the offence was committed, the importance and value of the subject of the offence, and the gravity of the harm or danger caused. Quantity and strength are argued there. The argument is real, it is discretionary, and it operates inside the range rather than on the range.

Two further rules govern the arithmetic. TCK 61/4: where several qualified circumstances apply, increases are made first and reductions afterwards. TCK 61/7: the resulting sentence for an offence carrying term imprisonment cannot exceed thirty years.

Where a technical argument does change the paragraph

The first is the name itself. TCK 188/4-a lists families and their derivatives — synthetic cannabinoid and derivatives, synthetic cathinone and derivatives, synthetic opioid and derivatives, amphetamine and derivatives. Whether a particular compound is a derivative of a listed family is a chemical question, and where the compound is a recent one it is a genuinely contested one.

The second is TCK 188/6. Where the substance is one whose production requires official permission, or whose sale depends on a doctor's prescription, and which produces a narcotic or stimulant effect, the same paragraphs apply — but the penalty may be reduced by up to half. Whether the report describes a controlled drug or a prescription medicine is therefore worth more than any argument about strength.

A third route belongs to the court rather than the laboratory. Under TCK 191/8, where it emerges during the prosecution of a TCK 188 or TCK 190 case that the conduct falls exclusively within TCK 191 — use, or purchase, acceptance or possession for use, punished by two to five years — the court gives a decision deferring the announcement of the judgment under that article. What the report records about quantity and packaging is part of what makes that finding available.

Challenging a report is not a speech at the hearing. It is a sequence of steps the Code already provides, most of which have to be taken in order and on time.

The moment the Code gives you

CMK 67/5: once the examinations are complete, a period is fixed for the prosecutor, the participant, the suspect or defendant and counsel to request a new expert examination or to state their objections. If those requests are refused, a reasoned decision must be issued within three days.

Notice what that provides. A refusal has to be reasoned, and it has to be in writing. A reasoned refusal is something an appeal can be built on later. An unmade request leaves nothing behind at all.

Your own specialist

CMK 67/6 allows the prosecutor, the participant, the suspect or defendant and counsel to obtain a scientific opinion from a specialist — about the event, for use in the preparation of the expert report, or about the report once it exists. Under CMK 68/3, that specialist can be summoned to give explanations at the hearing on the same terms as the court-appointed expert.

Objecting to the expert rather than the report

CMK 69 applies the grounds for recusing a judge to experts. The name and surname of a court-appointed expert must be notified to those entitled to challenge, unless there is an impediment. The person challenging must state the reason and the facts relied on. During the investigation stage a challenge the prosecutor does not accept is examined by the sulh ceza judge; during the trial it is examined by the court hearing the case.

What is examined, in practice

• The appointment decision (CMK 66/1) — which questions were put to the laboratory, and which were not.
• The seal and count records (CMK 66/7) — whether what was seized is what was examined, and what happened in between.
• The body of the report (CMK 67/1) — whether the operations performed are set out, or only the conclusion.
• Dissent (CMK 67/2) — whether more than one expert signed, and whether disagreement was recorded with reasons.
• Overreach (CMK 67/3) — whether the report characterises the conduct instead of the substance.
• What remains — whether enough sample is left for a second examination to be possible at all.

And CMK 68/1: the court may order the expert to be heard at the hearing at any time, and may summon the expert at a party's request. A report is easier to test when the person who wrote it is in the room.

The report is in Turkish, and the interpreter duty is narrower than people assume

CMK 202 requires that, where a defendant does not know Turkish well enough to express themselves, the essential points of the accusation and the defence at the hearing be interpreted by a court-appointed interpreter. The same applies to a suspect heard during the investigation, where the interpreter is appointed by the judge or the prosecutor.

The duty is to the essential points of what happens at the hearing. It is not a duty to translate a technical annex line by line. If your defence turns on what a chromatography table says, arrange for the report itself to be gone through with you in a language you read. Assume that will not happen by default.

CMK 202/4 gives a separate right: after the indictment is explained, and after the closing opinion is delivered, a defendant may make an oral defence in another language in which they can express themselves better, choosing an interpreter from the official annual lists. The Code states plainly that the cost of that interpreter is not met by the Treasury.

A second report, about your body, under different rules

Where a sample was taken from you, that is a separate legal act with its own conditions. CMK 75 governs internal body examination and the taking of blood or comparable biological samples from a suspect or defendant. The decision belongs to a judge or court, on the prosecutor's or the victim's application or of its own motion; where delay is prejudicial the prosecutor may decide, but that decision must be submitted for judicial approval within twenty-four hours, and the judge decides within twenty-four hours. Decisions that are not approved are void, and evidence obtained under them cannot be used.

Three further limits: the intervention must carry no danger to the person's health (75/2); it may be carried out only by a physician or another health professional (75/3); and no internal body examination and no sample may be taken where the offence carries an upper limit of less than two years' imprisonment (75/5). These decisions are open to objection (75/6).

What runs alongside the file

Two things are happening at the same time and are decided outside the criminal court. A travel ban imposed as a judicial-control measure keeps you in Türkiye while the report is written and argued; and a conviction under TCK 188 has consequences for residence and for later entry that the criminal court does not rule on. Neither is a reason to hurry the technical work, but both are reasons to know the timetable rather than wait for it. Ask early that your consulate be notified, and keep the family informed in a language they read — the people who instruct counsel are usually not the people in custody.

If you are already outside Türkiye, note that the report does not wait for you. The period under CMK 67/5 runs whether or not you have seen the document. Counsel holding a copy is the only reliable way to be inside it.

What this page cannot tell you is whether the report in your own file is wrong. That is answered by reading the appointment decision, the seal records and the report together, and none of those are public documents. Anyone who says a report is defective before reading it is guessing — and the guess costs you the window in CMK 67/5.